The subject matter disclosed herein relates to a combustion system, and more specifically to a combustion system with an air passage defined by a liner and a flow sleeve, and a venturi generally restricting and diffusing airflow in the air passage.
Gas turbines include a compressor that supplies compressed air to a combustor. Specifically, compressed air is supplied through a gap or space between a liner and a flow sleeve of the combustor. There are typically different types of structures that may be disposed within the space between the liner and the flow sleeve such as, for example, a crossfire tube or a flame detector. Flow disturbances, which are typically referred to as wakes, may be created as the compressed air flows past these structures.
A wake is a zone of aerodynamic disturbance created by a component such as a crossfire tube, and represents a region of re-circulating flow located downstream of the structure. The presence of wakes in the space between the liner and the flow sleeve may create several issues. For example, fuel injected downstream of the structure may be pulled into the wake. Fuel may accumulate in the wake and cause flame holding, which in turn decreases gas turbine performance. Wakes may also cause hardware issues in the gas turbine, which may potentially cause the gas turbine to shut down. Wakes may also create a higher pressure drop across the liner. In an effort to improve features such as gas turbine flame holding performance, a relatively wake free flow field is provided.